Improvement in the manufacture of wrenches



didnt tdt JGHN RICHARDS, OF PHILADELPHIA, PENNSYLVANIA.

Lettere retten Ne. 109,665, dead November 29, 1870.

IMPROVEMENT iN THE MANuFAcTuRE oF wRENcHEs,

The Schedule referred to in these Lettera Patent and making part of the same.

I, JOHN RICHARDS, of the city and county Q f Philadelphia, in the State of Pennsylvania, have invented a certain improved Method of Making \V'renches, of which the following is a specification.

Nature and Object of the Intention..

This invention relates to an improved Inode of inannfactnring common wrenches, and to a combination of soft iron and hardened steel in such Wrenches, giving greater strength and endurance, without increasing the amount ot material or the cost of their manutac- Description of thc Aeconqmny'ing Drawing..

Figure 1 is a side vieiv of a'common Wrench, constructed on my` improved plan, and

Figure 2 is an edge View of fig. 1.

Similar letters of reference indicate corresponding parts.

Genera-Z Description.

lhe central part, a, is of soft or malleable iron, made of' a sufficient thickness to form a proportionate handle for the wrench.

' rlhis part is parallel in its thin section, and can be punched from sheetsor plates of iron prepared for the purpose, the outline conforming to rig. 1, or other modification to suit diagonal or square nuts or bolts or it can be made wthan inclosed eye when greater strength is required.

The scales or plates mand n are 0f steel, having la thickness equal to aboutone-half of' the cent-ral plate These plates can also be punched from plates of steel, with an outline to correspond with th'e head of' the Wrench.

These plates or scales are thcn welded or blazed to the part a, giving the form shown in fig. 2.

The head of' th e wrench is then hardened and teni'- pered in the usual manner, the central part between the dotted lines, lig. 2,' and the handle, remaining soft, While the hardened facings'prevent wear, and give great strength to the jaws, as will be readily understood by those skilled in such arts. V

The plates m and a can be made of iron when it is not necessary to harden them, the whole being malleable and soft, or, when composed entirely of iron, the Whole can be case-hardened in the'usual manner to prevent surface-wear.

The proportionate thickness ot the central part a 0r the plates maud n can, of course, be varied to snit the conditions of use without affecting the nature of the invention. e

A wrench formed in this manner may also be casehardened. by the usual process, by which means the plates m anda will be tempered throughout, and the malleable part a be only surfacediardened to prevent Wear.

Ola/im Witnesses WM. S. KELLEY, A. O. UMs'rnD. 

